Summary
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1.
Echolocating bats use echo delay as the primary cue to determine target distance. During target-directed flight, the emitted pulses increase in repetition rate and shorten in duration as distance decreases. To determine how these parameters affect the delay tuning of neurons in the auditory cortex of the awake bat, Myotis lucifugus, we examined the responses of 104 delay-sensitive neurons as the pulse repetition rate (PRR) and duration were independently varied. Stimulus duration of 4, 2 and 1 ms and PRR of 5–100/s were used for both the pulse and echo to determine delay sensitivity. These parameter ranges span those used during the search, approach, and the initial terminal phases of echolocation.
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2.
As the stimulus duration was shortened, the range of PRRs for delay sensitivity was extended to higher rates in 41% of the neurons, narrowed or disappeared in 40%, and remained unchanged in 4%. The remaining 15% were not categorized since it was not possible to determine a trend in which the range of delay-sensitive PRRs changed with stimulus duration.
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3.
Three types of tracking neurons (i.e., neurons that change their best delay during target-directed flight) were found. For the first type, the best delay (BD) shortened with shorter stimulus duration, for the second type, BD shortened with both shorter stimulus durations and higher PRRs, and for the third type, BD shortened with higher PRRs.
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4.
These results suggest that the stimulus parameters of sonar emission influence delay tuning and hence processing by cortical neurons in FM bats.
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References
Berkowitz A, Suga N (1989) Neural mechanisms of ranging are different in two species of bats. Hearing Res 41:255–264
Feng AS, Simmons JA, Kick SA (1978) Echo detection and target-ranging neurons in the auditory system of the bat Eptesicus fuscus. Science 202:645–648
Feng AS, Hall JC, Gooler DM (1990) Neural basis of sound recognition in anurans. Prog Neurobiol 34:313–329
Gooler DM, Feng AS (1992) Temporal coding in the frog auditory midbrain: The influence of duration and rise-fall time on the processing of complex amplitude-modulated stimuli. J Neurophysiol 67:1–22
Griffin DR (1958) Listening in the dark. Cornell University Press (reprinted), Ithaca, NY
Griffin DR, Webster FA, Michael CR (1960) The echolocation of flying insects by bats. Animal Behav 8:141–154
Habersetzer J, Vogler B (1983) Discrimination of surface-structured targets by the echolocating bat Myotis myotis during flight. J Comp Physiol 152:275–281
Hartridge H (1945a) Acoustic control in the flight of bats. Nature 156:490–494
Hartridge H (1945b) Acoustic control in the flight of bats. Nature 156:692–693
Henson OW Jr, Bishop A, Keating A, Kobler J, Henson M, Wilson B, Hansen R (1987) Biosonar imaging of insects by Pteronotus p. parnellii, the mustached bat. Natl Georg Res 3:82–101
Mendelson JR, Cynader MS (1985) Sensitivity of cat primary auditory cortex (AI) neurons to the direction and rate of frequency modulation. Brain Res 327:331–335
Moss CF, Schnitzler H-U (1989) Accuracy of target ranging in echolocating bats: acoustic information processing. J Comp Physiol A 165:383–393
Novick A, Griffin DR (1961) Laryngeal mechanisms in bats for the production of orientation sounds. J Exp Zool 148:125–146
Novick A, Vaisnys JR (1964) Echolocation of flying insects by the bat Chilonycteris parnellii. Biol Bull 127:478–488
Obrist M (1989) Individuelle Variabilität der Echoortung: Vergleichende Freilanduntersuchungen an vier vespertilioniden Fledermausarten Kanadas. Dissertation, Ludwig-Maximilians-Universität, München
O'Neill WE, Suga N (1982) Encoding of target range and its representation in the auditory cortex of the mustached bat. J Neurosci 2: 17–31
Pinheiro AD, Wu M, Jen PH-S (1991) Encoding repetition rate and duration in the inferior colliculus of the big brown bat, Eptesicus fuscus. J Comp Physiol A 169:69–85
Roverud RC, Grinnell AD (1985) Discrimination performance and echolocation signal integration requirements for target detection and distance determination in the CF/FM bat, Noctilio albiventris. J Comp Physiol A 156:447–456
Sales G, Pye D (1974) Ultrasonic communication by animals. Chapman and Hall, London
Schnitzler HU (1968) Die Ultraschall-Ortungslaute der HufeisenFledermäuse (Chiroptera-Rhinolophidae) in verschiedenen Orientierungssituationen. Z Vergl Physiol 57:376–408
Schnitzler HU, Henson OW (1980) Performance of airborne animal sonar systems: I. Microchiroptera. In: Busnel RG, Fish JF (eds) Animal sonar systems. Plenum, New York, pp 109–181
Schnitzler HU, Kalko E, Miller L, Surlykke A (1987) The echolocation and hunting behavior of the bat, Pipistrellus kuhli. J Comp Physiol A 161:267–274
Simmons JA (1973) The resolution of target range by echolocating bats. J Acoust Soc Am 54:157–173
Simmons JA (1987) Acoustic images of target range in the sonar of bats. Naval Res Rev 39:11–26
Simmons JA, Lavender WA, Lavender BA, Doroshow CA, Kiefer SW, Livingston R, Scarllet AC (1974) Target structure and echo spectral discrimination by echolocating bats. Science 186:1130–1132
Suga N, Horikawa J (1986) Multiple time axes for representation of echo delays in the auditory cortex of the mustached bat. J Neurophysiol 55:776–805
Suga N, O'Neill WE (1979) Neural axis representing target range in the auditory cortex of the mustache bat. Science 206:351–353
Suga N, O'Neill WE, Kujirai K, Manabe T (1983) Specificity of combination-sensitive neurons for processing of complex bio-sonar signals in auditory cortex of the mustached bat. J Neurophysiol 49:1573–1626
Sullivan WE (1982) Neural representation of target distance in auditory cortex of the echolocating bat Myotis lucifugus. J Neurophysiol 48:1011–1032
Tanaka H, Wong D (1992) The effect of stimulus duration on the temporal-tuning properties of cortical neurons in the FM bat. Assoc Res Otolaryngol 15:141
Whitfield IC, Evans EF (1965) Responses of auditory cortical neurons to stimuli of changing frequency. J Neurophysiol 28:655–672
Wong D (1984) Response properties of auditory neurons in the superior colliculus of the bat, Myotis lucifugus. Hearing Res 16:261–270
Wong D, Shannon SL (1988) Functional zones in the auditory cortex of the echolocating bat, Myotis lucifugus. Brain Res 453:349–352
Wong D, Maekawa M, Tanaka H (1992) The effect of pulse repetition rate on the delay sensitivity of neurons in the auditory cortex of the FM bat, Myotis lucifugus. J Comp Physiol A 170:393–402
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Tanaka, H., Wong, D. & Taniguchi, I. The influence of stimulus duration on the delay tuning of cortical neurons in the FM bat, Myotis lucifugus . J Comp Physiol A 171, 29–40 (1992). https://doi.org/10.1007/BF00195958
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DOI: https://doi.org/10.1007/BF00195958